In treating glaucoma the clinician attempts to lower the intraocular pressure (IOP) but, since it is not constant, a single measurement during a visit to the ophthalmologist may be unreliable. The measurement of the IOP at the patient's home has been advocated but has been hampered by the lack of an instrument that can be used reliably and safely by the patient alone. A self-tonometer, recently developed by academic researchers, has been successfully implemented in clinical research and cited among the progresses in the priority areas set in the NEI National Plan. The goal of the proposal is to make the self-tonometer available to the ophthalmic community by converting the prototype into a commercial product. Phase I will consist of introducing a microprocessor to control the operation, register and check the readings, provide feedback to the patient and archive the IOP, time and date until the data is processed at the clinician's office. A computer controlled pressure generator will also be developed. The upgraded version will be tested and its function compared to that of the existing prototype. Phase II will be dedicated to specifying, designing, developing and testing a commercial prototype.